X-ray system.



H. G. SNOOK,

X-RAY SYSTEM.

APPLICATION FILED JULY 20, 1907 Patented Apr. 5, 1910.

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5 vwa ntoz wza aitoznu) I H. G. SNOOK.

X-RAY SYSTEM. APPLICATION FILED JULY 20, 1907.

Patnted A r.5,1910.

3 SHEETS-SHEET 2.

'H. G. SNO0K.

X-RAY SYSTEM. 7 APPLICATION FILED JULY 20, 1907.

Patented Apr. 5, 1910.

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1 @4 44 Mam so that the mtens ty of excitation s a maxi To all whom it may concern:

citizen ofthe'UnitedStates, residing at ll'iiladelphia, county of'Philadelphia, anklemmnsmms PATENT canton.

HQMER'CLYDE SNOOK, or PHILADELPHIA, PENNSYLVANIA, AssIG oR TQROENTGEN MAN FACT RING company, A conrozeerron. OF PENNSYLVANIA.

"i 'E 'ipmatioii-mea July 2o,'1907. Serial Nmseasoa' Be itknown'that I HOMER CLYDE SNooK,

State of: Pennsylvania, have invented certain new anduse-ful Improvements in X-Ray Systems, of which the following is a specification. .v

. My invention relates to a system for ro ducing X rays, and has particular'reference to the production of very intense X-rays with a maximum etficiencyof conversion. My'invention res des in means for excit ng an 'X-ray tubeat a much higher current density than has been heretofore practiced in the art, with greatly increased usefulness, both in the direction of greatly reducing pe-. 'riods of exposure, and rendering visible the interior of denser orfxthicker masses, and otherwise;

in' which the transformer has minimum magnetic leakage, n combmatlon with a rectifyingsWitch-driven in synchronismand defi nite phase relation with the current supply, preferably by mechanically connecting the rotating member of the switch to the rotat ing member of a current generator. These features, along with features of the rectifying switch contribute to efficiency of conversion in' the X-raytube, by preventing inverse-discharge in the tube; and by my 'sys te1n 'all.0ftl1e current waves are passed 'throughjthe X-ray tube all in-thesame direction, and; without any inverse discharge,

For an illustrationof one of the forms my invention-may take reference is to -be hadto the accompanying drawings, in wlnch:

.,Figure 1 isa diagrammatic iew illustrat. mg the apparatus-andjcircult arrangements fofthe systen1. F1g.'2 IS a vertical sectional view, partly in elevation oftheli'i fh potenof a secondary choke coil.

Referring to Fig. 1 Z, Z- are'jthe tors of an electric supply circuit, in thisiIIjstance of direct current. A s ta'rting box,

Specifica tion'of Letters Patent.

- nner SYSTEM.

Patented-Apr. 5,1910.

shown conventionallyat-s, intervenes in the direct current side of the motor generator or lnvert'ed rotary G.

alternatingcurrent"v genera-to r. If an invertedrotary, it comprises a; direct current armature'having suitable tapsftaken 01f to slip rings in a well known nannen In either case, the alternating current is delivered by i If a motor generator, it comprises a direct current IIIOlTOT'dIlVIIIg an switch arm or' lever 6 serves to cut in or out u v 5-. more or,1ess of the non-inductive resistance- My nvent on resides m an X-ray system "Lfor controlling the current strength inthe transformer primary circuit.- As 'showi' the transformer T has a closed magneticv circuit,

and this ist-he referred form, though other circuit type the mutual induction between.-

small. This insures a shifting of'pha'seof ,the primary and secondary windings i's mad e very great,-the magnetic leakage be ng very l secondary. current with res met to secondary electromotive .force, which is only slight, if

anything. With this type oftransfornier the magnetizing current at all times isE-a minimum, thus requiring less volt-ampere capacity and output of the. machine G. Rea

actance or choke coils D, D are connected in 'serieswith the secondary of the transformer..- These reactances have no iron presentand f ofier aself-induction to'any high'frequency oscillations, preventing'such high frequency oscillations/running "hack to the secondary winding and puncturing the insulation theres axially short coils, which might; be called pancake coils, connected. in series with each other but t'heseparate 0011s or wlndmgs are sowidely tseparated from each other, either by'air or su table dielectric, such as ,w'ax, r se t,

of or causing other breakdown. .These re j dctances D, :D arepreferably constructed of rmixtures of the isame, that-the capacity between neighboring coils 1s. s-

lcoils. This construction is represented Fig. i where the pancake coils f f are shown were placed close together, or if the winding was one long continuous. coil, the oscillations might succeed in passing the coil to the sec-- ondary S of the transformer without passing through the conductor of the reactance' in edge View and separated by a suitable di-I electric material 9 further advantage that the self-induction as regards the low transformer frequency is a minimum, while as to high'frequency oscil-' chronism with the current of .cither the pri- -the inverted rotary and carried by the spindle J are four memary or secondary of the transformer T.'

From the ole changing switch E the conductors 'i lea'd to-the terminals 'ofthe ray tube X, whose cathode-is la and whose anode is' j. An ammeter. F is connected in series between the conductor i and the oathode kand serves to measure the amount of current passed through the tube X. This ammeter F may be constructed similarly to'a DArsonval galvanometer'ormeter as modified in accordance with Letters Patent of the United States No, 758,957.

Referring to Fig. 2, a bench or base H, of wood or other suitable material, serves to support the high potential rectifying or pole changing switch,the transformer T, (contained, along with the reactances D, D

in themetal transformer case I) and the motor generator or inverted rotary G. In Flg. 2 G is shown as an inverted rotary receiving direct current and delivering alternatmg current. A wooden spindle or shaft J has metal shaft terminals 'm'm having bearings 01 a supported by the end walls 0 o of the wooden covering or. casing for the high potential pole changing switch 13].. One

of the terminalshafts m is connected by an insulating coupling g with 'the shaft 9 of Extending through ta-llic rods or wiresr, t,iu and o incased in rubber or other insulating-covering and sup?- port w, In Fig. 2 the conductors t and are shown in vertical position while the conductors 1" and u are shown horizontal, the pairsbeing always at right angles to each other.. The four conductors and-then coverings and the wooden spindle- J are all mechanically balanced 'so that the center of gravity of the moving system is in the axis of the moving spindle J. Vertically ex,

tending rods or members 1 and 2 of insulating material are arranged parallel with each other and sup ort similar conducting arcs 3 and 4 dispose above and below the spindle There are four pairs of vertical supports '1 and '2. supporting similar and. similarly v "lajced conducting arcs 5, 6-7, 8 and 9,.10.

. he conducting arcs 3'and 9 are connected together ,byyconductor 11 from which leads one of the two conductors 7;. Conducting The separation of the" .coils f, f as described, is productive of the" through the insulatin tube 14 through the cover of the oil tank from one terminal of Similarly, the conducting arcs 8 and 1-0 are which communicates the conductor h led up through the insulating tube 15 from the tank I forming the other terminal of the secthe inverted rotary G the conducting rods 1", t, u' and o rotate in front of their-respective conducting arcs and in close proxunity theretoftliough' notrin actual mechanical contact therewith. The angular extent of the, conducting arcs from tipto tip is slightly ence of the secondary S exists. For this of mica, lass, or other suitable material intervenes etween them and extends well u toward the spindle J. The same great di ference of potential exists between the neighboring conducting arcs 3, 5 and 7, 9 and between each pair is disposed a similar insupotential switch, the inverted rotary and the transformer, as shown upon the bench or support H, is a most convenient and advantageous one, and particularly when it is desired that .the apparatusshall be portable or movable from room to room, in which case rollers or casters are supplied 11 on the feet of the bench H. The ammeter 4 is conveniently disposed upon the top of the 0:15-

tential switch.

' The operation is as follows: The operator closes any suitable switch whereupon the conductors Z, Z are thrown, into communication with a source of current, and then the lever of the starting box'sis moved to cut out resistancein a well known manner, whereupon the motor generator or inverted rotary sets the spindle J into o eration. Upon clos-. ing thereversing swit A by hand, either in the one position or the other, the trans former T is energized and the secondary. winding S delivers current at high potential to the lower conducting arcs of'the mechanical rectifier or. high potential switch E;

arcs 4 and '6 are the secondary .S of the transformer T.

arcs 5 and 7 are connected together by con 4 is also connected the conductor it led up connected together by the conductor 15 with ondary S. As the spindle J is rotated byless than 90 degrees. Between the conductingarcs 4, 6 and 8, 10 the full potential differ- 5 reason a heavy insulating screen 111 composed lating screen y, a. The disposal of the high mg or wooden covering K for the high pocomes up to full speed. This simultaneously {The E, through upper conducting arcs, deliversv current to the X-ray tube -X through the ammete'r F always inthe samedirection, that "is .to say, all of the half waves of the alternating'ourrent are passed through the tube X and all of them always in "the same direction,

If it is found at starting that the direction of the current through the tube X is wrong, as mani- 1 through the cross'connectors r, t, (1,0,4) of the O,"through crossconne'ctor 1 to the are 10' fested by a mere glance at'the tube, the op: erator needs simply tothrow the switch A proper dipotential' switch are-slightly less than 90 degrees (the inverted rotary G being a'fourpolegmachine) insures that a otential wave- ;sha'll exist in the secondary interval of time before-any currentpasses switch .13 to the tube X. These. features of very" small, if any, phase displacement be tween current and electromotive forcein the secondary S and'the conducting arcs of angular length slightly, less than a half wave of current. guarantee that there will beno inverse discharge in the :tube X, each of these features contributing to that end. The operator eziercisescontrol of the secondary potential by adjusting the switch lever n, to include-more or less primary turns; and he exercises control as .to current strength in the'primary'P by adjusting the non-induct ive resistance L.

. VVith the parts of the .switch E in'the position shown in Fig. 2, the transformer T is delivering current at the maximum of -a half wave through the conductor ill. to the are 6 through the cross connector ft to the arc 5,.and'thencelby conductors 12 and i toone terminal of the tube, the returnfbeing" through'the conductor '4', conductor 11 to are andthence by conductor h to the other ter- .minal of the secondary. Bythe arrangement shown the high potential switch-incur bers r, t, u and v r-otate'in synchronismwith the alternating current delivered by G andthe spindle Jis secured by the coupling p in definiteangular position with respectto the windings of G delivering alternating current. "This" phase relation'or angular position may be adjusted by the coupling 7;.

- Obviously, the motorg'enerator or inverted rotary G. may be placed at adistance from the switch E and the spindle J driven by a for a slight synchronous motor deriving its current from G,-though such arrangementis not so effective in preventing inverse discharge in the tube as where a mechanical connection is employed. Obviously, also the connec-' tion between the shaft 9 of the machine G with the spindle J neednotbe a direct me- 'chani cal"one,but may be an indirect niechanical-"one as by belt, gears, chain, or other suitable means, itbeing necessary only to insure synchronisn of the spindleJ with the;

shaft g, and in the proper angular phase re latioin or the spindle J may be driven by a any suitable lnotor, as a direct current motor or an asynchronous alterating current motor,-

outofste Such.a device maybe afield having I po es excited by alternating current, having arotating member having wound or tors Z, Z may communicate with an alternat-' .so] and ada'in'ping or control deviceapplied' to --the spindle"J to prevent'huntingor getting 'unwound poles. Furthermore, the'conduc ing current and supply current to an in-n duction motor to drive an' alternating cur rent generator of a different'frequency from the supply, the spindle J being connected to the shaft of the alternating, current generator. Or the-induction motor may drive the spindle J and a'synchronizing device, such as'a small synchronous motor, or the device. just previouslydescribed, may act upon the spindle J to keep it in synchronism or, proper; speed. It is obvious alsothat a source of direct current may be employed in 'connection with the transformer primary, a pole changing switch and interrupter beingin cluded in the circuit and driven or operated at desiredspeed, with afhightension pole changing switch or rectifier in the secondary circuit synchronous with the switch and interrupter in the primary circuit.

While 'the switch E is shown with only three insulating barriers and with the-con each other, it is to be understood that the-two pairs. of conducting ;arcs may be shifted around through '90-degrees and the rotating cross connectors all arranged'in. line witheach other, and in such case five insulating barriers will-be required. I

j What I claim is 1; In an 'X-ray system, the combination with a source of fluctuating or alternating current, of ahigh tension transformer "having very small magnetic leakage, an X-ray ducting arcs all in line and the pairs of rotating cross connectors at 90 degrees with tube, and a synchronous rectifying switch comprising conducting arcs and associated cross connectors, the angular extent of an arc corresponding with a ,1ength sli htly 'less' than a current wave, whereby a-l current waves arepassed through said tube and all in the same direction, and whereby Iinverse discharge in said tube is prevented;

2.. In an X-ray system, the combination controlling the passage of current through said tube, said switch having conducting arcs of angular extent corresponding with substantially an entire current wave.

4:. The combination with a source of fluctuating current, of a high potential rectify ing switch comprising conducting arcs and cooperating cross connectors, means for cans; ing relative rotation between said, arcs and cross connectors in synchronism with said current, said conducting arcs of said switch having an angular extent" corresponding with a length slightly l'ess than a current wave.

5. In an X-ray system, the combination with a source of 'alternatingor fluctuating current, of a high tension transformer supplied thereby, said transformer having small magnetic leakage, an X-ray tube, and a rectifying switch, comprising conducting arcs of substantial angular extent and associated rotating cross connectors, directing all of the current waves through said tube and all in the same direction.

6.'In an X-ray system, the combination with a generator of fluctuating or alternat ing current, of a transformer having small magnetic leakage, an X-ray tube, and a rec tifying switch fordirecting all the current waves from said transformer through said tube and all in the same direction, the rotating member of said switch being driven in definite mechanical relation with the rotating member of said generator. 7. In an X-ray system, the combination with a generator of fluctuating or alternat-' ing current, of a transformer having small magnetic leakage supplied thereby, an X-ray tube, and a rectifying switch directing all the current waves from said transformer through said tube, the rotating switch member being driven in definite mechanical relation with the rotating member of said generator. I

8. In an X-ray system, the combination with a generator of fluctuating or alternat ing current, of a transformer, an X-ray tube, and a rectifying switch directing all of the current waves from said transformer and substantially all of each wave through said tube, the rotating member of said switch being driven in definite mechanical relation 'with the rotating member of said generator.

9. Inan. X-ray system, thecombination with a generator of alternatlng or fluctuating current of a high tension transformer having small magnetic leakage, an X'-ray tube,*and a high potential -rectifying switch directing all of the current waves from said transformer through said tube and all in the samedirection, the rotating member of said switch being driven in'definitemechanical relation with the rotatingrmember of said generator.

10. In an X-ray system, the'combinatlon with a generator of fluctuating or alternating current, of. a transformer having small magnetic leakage, an 'X-ray tube, and a rec tifying switch directing all the current waves from said transformer through said tube and all in the same direction, the rotating member of said switch being mechanicaIIy connected with the rotating member-ofsaid. generator.

11. In an X-ray-system, with a generator of alternating or fluctuating current, of a high tension transformer having small magnetic leakage, an X-ray tube, and a high potential rectifying switch directing all the current waves from said transformer through said tubeEand all in the same direction, the rotating member of said switch being mechanically connected with the rotating member of said generator.

12. In an'X-ray system, the combination with a current supply, of a dynamo electric converter delivering fluctuating or alternating current, a transformer deriving current from said converter, an X-ray tube, and a rectifying switch directing all the"'cu'rrent" waves from said transformer through said tube, the rotating member of said switch being driven in definite mechanical relation with the rotating member of said converter.

13. In an X-ray system", the combination with a current supply, ofa dynamo electric converter delivering alternating or fluctuating current, .a transformer, an Xray tube, and a rectifying switch directing all the current waves from said transformer through said tube and all in the same direction, the rotating member of said switch being driven in definite mechanical relation with themtating member of said converter.

14. In an X-ray system, the combination with a current supply, of a dynamo electric converter delivering fluctuating or 'alterthe combination nating current, a transformer having small magnetic leakage, an X-ray tube, and a rectifying switch directing substantially all the energy from said transformer through said 60. l barrier between neighboring arcs "of-different pairs atdifiierent'. potentials, and rotat. ing "cross connectors cooperat ng wlth v sa d 1 15. In an- X -ray system, thezcombination with a current supply, of adynamo electric 'converter delivering fluctuating or alternating current, a "transformer, an 'X-ray tube,- and a rectifying. switch directing all the current, waves from said transformer througlrsal'd tube, therotatmg memberof said switch belng mechan cally connected with the rotating member of said converter.

v 16. In an X-ray system, the combination Wlth a generator of fluctuating or alternating current, ofa transformer havin smallmagnetic'leakage, an X-ray tube, an a rectifying switch directing substantially all of the energy from said :transformer throu h said tube and all in the same direction, t e rotating member of said-switch beingdniven in definite mechanical relation-with the retating member of said generator.

17. In an X-ray system, the combination with a generatorof fluctuating. or alternating current, of a 'trans former ha'vin small] magnetic leakage,{an X-ray tube, an' a rectifying switch directing all fthe currentwaves from said transformer throughsa-idtube and allin the' 'samedirection, the. retatmg member of said switch being driven indefinite mechanical relation with the rotating member-of said generator.

'18. In combinationwith a source of alternating or fl uctuating current, a synchronously driven switch comprising pairs-of conducting a res and cotiperatlngeross connectors dlsposed at 90, degrees wlth respect toeach other, the'moving member of said switch bein mechanically coupled to the rotating inem er of said source of current and so related to the eurrentfrom fsaid source that 90 mechanical degrees in said switch corre-fi pond with 180 electrical degrees. of said (current. I

. 19. In a high I 20. In, a high potentialelectric switcih, pairs of; opposed conducting arcs, an insulating barrier disposed between neighbor'- ingarcs of different pairs,and rotating cross connectors cotiperatingwith, said arcs.

21.'In ahigh-potential electric switch,

I pairs ofop osed arcs, the arcs of the differ ent pairs isposed *in'alinement with each other, an insulating barrier between neighborin arcs of diiferent pairs, and rotating cross connectors coiiperati-ng with said arcs and disposed at right angles toeachother.

22, Infahigh potential rectifying switch, four pairs 0 Opposed arcs, arrnsulating potential electric, switch pairs of opposed conducting arcs, said pairs beingdisposed in alinement with each other, and coiiperating rotating cross connectors disposedatright angles to each other.

four pairs of opposed arcs, the arcs of the 23. In ahigh potential,rectifyingswitch,

different pairsbeing disposed in alinemen't wlth' each'other, and three insulating barriers disposed respectively between neigh-. boring arcs at different potentials, and four rotattillgjfcross I connectors coiiperating w itlr said arcs, the neighboring cross connectors being disposed at right angles with respect to each other..

- 24. In combination-withsource of flucftuating current, a synchronously driven rectifying switch comprising opposed pairs of conducting arcs having an angular extent correspondingjto slightly less than the current wave, and cooperating rotating cross connectors. disposed-at right angles to each other, said cross connectors bein supported and driven by aninsulating sha t, and-said cross connectors being themselves insulated throughout nearly their entire lengths.

25 In combination with a' source of fluctuating current, a synchronously driven rectifying switch comprising pairs of opposed conducting arcs, said pairs beinmdisposed in alin'ement with each other, and cotiperating rotating cross connectors, an insulating shaft for supporting and driving said cross connectors sa1d cross connectorsbemg them selves 'insu ated throughout nearly their enring with said arcs, neighboring cross .con- "nectors' being disposed at right angleswith respect to each other.

rectifying switch,

27. In a high potent1al' rectifyingswitch,

pairs of opposed conducting arcs, an insulatlng barrier. disposed between neighboring arcs, of different pairs, an insulating shaft,

and'cross connectors cooperating with said arcs rotated by said shaft' and nsulated throughout nearly: their entire lengths.

28. In a high potential rectifying switch,

pairs of opposed arcs, the arcs of the difler- I ent pairs. disposed inalinement with each other, aninsulating barrierbetween ne1gh-' boring arcs of different pairs,*an insulating shaft, and cross connectors cooperating with said arcs rotatedby said shaft and insulated throughout nearly their entire lengths.

29. In an X-ray system, the colnblnatlon transformer having small magnetic leakage with a generator of fluctuating current, of a andderiving current from said generator, an X-ray tube, a high potential rectlfylng secondary and said X-ray tube for diroting all the current waves through said tube and all in. the same direction, and means for driving the rotating: switch element indefinlte angular relation with thc'rotatlng element of said generator.

30. In an X-ray' system, the combination with a generator of fluctuating current, of transformer having small 'ma netic leakage and deriving current from sait generator, an X-ray tube, a'high potentialrecti fying switch. intervening between said transformer secondary and said 'X-ray tube for directing all the current'waves through said tube and all in the same direction, and a mechanical connection between the rotating elements of said generator and of saidswitch.

' 31. In an'X-ray system, the combination with a generator of fluctuating 'eurrent, of

' a transformer deriving current therefrom,

' an X-ray tube, a high potential rectifying switch, said switch comprising pairs of conducting. arcs and cooperating connectors, said arcs and connectors bein rotatable with respect to each other, said switch directing all the current waves through said tube and all inthe same direction, and means for; driving the rotatable switch element 1n,

definite mechanical relation with the rotating element of said generator.

32. In an X-ray system, the combination with a generator-of fluctuating current, of

a transformer having small magnetic leakage deriving current therefrom, an 'X.-ray

tube, a high potential rectifying switch, said switch comprising pairs of conducting arcs and cooperating connectors, said arcs and connectors being rotatable with respect to each other, said switch directing all the current waves through said tube and all in the same direction, and means for driving the rotating switch element in definite mec han ical relation with the rotating element of said generator."

33. In a high potential rectifying switch, cooperating relatively rotating arcs and connectors, an insulating driving shaft, and barriers between arcs and connectors subjected to widely different potentials.

34. In a high potential rectifying switch, cooperating pairs of arcs and connectors, means for rotating said arcs and connectors with relation to each other, barriers between arcs subjected to widely different potentials, the arcs or connector of one pair being disposed mechanically at an angle with the arcs or connector of another pair corresponding with the angle of phase difference between the current waves to be rectified.

35.111 a high potential rectifying switch, 1

cooperating relatively rotating pairs of arcs at different potentia s.

BGJTIhe combination with a generator of fluctuating current, of a step up transformer having small-magnetic leakage and deriving device, ahigh potential rectifying switch intervening between the transformer secondary and said translating device for directing all the current waves through-said translati'ng device and all inthe same direction, and means for driving .the rotating switch element in definite angular relation with the rotating element of said generator.

37. The combination with a generator of fluctuating current, of a step up transformer having-small magnetic leakage and deriving current from said generator, a translating device, and a high potential rectifying switch intervening between the transformer secondary and said translating device for directing all'the current waves through said translating device and all in the same direction. I

38. The combination with a generator of fluctuating current, of a step up transformer deriving current from said generator, a .translating device, a high potential rectifying switch intervening between thetransformer secondary and said translating device for directing all the current waves 1 through said translating device and all in the same direction, and means for driving the rotatingswitch element in definite angular relation with the rotating element of said generator.

39, The combination with a generator of fluctuating current, of a transformer having small magnetic leakage and deriving current from said generator, a translating device, and a high potential rectifying switch intervening between the transformer secondary and said translating device for directing sub stantially all of each current wave through said translating device and all the current waves in the samedirection.

40. The combination with a generator of fluctuating current, of a step up transformer deriving current from said generator, a translating device, a high potential rectifying switch intervening between the transformer secondary and said translating de' vice for directing substantially all of each current wave through said translating device and all the current waves in the same ing switch element in definite angular relation with the rotating element of said gen- 1 erator.

1 In testimony whereof I have hereunto affixed my signature in the presence of the 3- two subscribing witnesses.

-HOMER CLYDE SNOOK.

WVitnesses i I ELEANOR T. MoCALn, I i ANNA E. STEINBOCK.

current from said generator, a translating direction, and means for driving the rotat- Disclaimer in Letters Patent No. 954,056.

ISOLAi'MEB- 954,056.H0mer Clyde Snook, Philadelphia, Pa. X-RA SYSTEM. Patent dated 7 April 5, 1910. Disclaimer filed December 31, 1915, by Snook-Roentgen Man afa ctaring Company, assignee by mesne assignments.

Enters this disclaimer:

To that part of the specification printed at page 3, lines 98 to 106, inclusive;

and reading as follows:

fIt is obvious also that a source of direct current may be employed in conn'ec-- tionwith the transfornier primary, a pole changing switch and interrupter being included in the circuit anddriven or operated atdesired speed, with a high tension pole changing switch or rectifier in the secondary circuit synchronous with the switch and interrupter in the primary circuit.

[Qflicz'al Gazette, J anaary 11, 1.916.] 

